Make sure that you have prescription meds enough to last for the duration of trip. Take along chargers for cell phones, cameras and other gizmos. Take glasses and any over the counter drug store stuff/personal items that may be hard to find. A good first aid kit and comprehensive tool kit with adhesives, duct tape, electrical, tape, iron wire ,screws and nuts, miniature screw drivers and a digital multi-meter. Keep the tool kit in the RV. If you don't have Tire Man or Borg tire valves installed, get them. Don't use screw-on extenders. A large skillet is handy for cooking on provided fire place.
Bug spray, paper plates and bowls, a water pail, and small funnels. Don't over pack clothes. Oh! Bring rain ponchos and umbrellas, charcoal briquettes and lighter fluid, small take-apart BBQ. Have a good GPS unit and know how to use it for planning for off ramps and merges, finding services, etc. Some GPS are RV'er oriented.